Alzheimer's Disease and Aggressive Behavior

Detailed information on Alzheimer's and aggressive behaviors including triggers for aggression and reasons for aggressive behavior.

Sometimes Alzheimer's or dementia patients seem to behave in an aggressive way. They may be verbally abusive or threatening, for example, or kick or pinch, or they may lash out violently at people or property. If such behavior occurs, you will probably feel distressed and anxious about the best way to cope.

Here are some possible explanations for the aggressive behavior:

  • A person with Alzheimer's disease or dementia may react in what appears to be an aggressive manner if they feel frightened or humiliated, or frustrated because they are unable to understand others or make themselves understood.
  • Someone may also become aggressive if their judgment and self-control have been eroded by dementia. They may be no longer be restrained by inhibitions learned in early childhood and forget how to behave appropriately.
  • Aggressive behavior sometimes seems to take the form of an over-reaction. The person may shout or scream or become very agitated as a result of what appears to be a very minor setback or criticism.
  • Any form of aggression is upsetting but it is important to remember that the person is not being aggressive deliberately. They will probably forget the incident very quickly, although the emotion which caused them to behave in that way may persist. You may take longer to forget the incident than they do.

Triggers for aggression and dementia in Alzheimer's patients

If you look carefully at the situations in which the person with Alzheimer's becomes aggressive and the events that lead up to the outburst, you may be able to identify the trigger and gain some understanding of what might be troubling them. Of course, it is not possible to analyze such a situation until it is over. But, once the heat of the moment has passed, you may be able to think about what happened and why.

If there seems to be no pattern to the behavior and it is becoming very difficult to manage, seek professional advice.

Possible reasons for a person with Alzheimer's or dementia behaving aggressively include situations in which they:

  • Feel frustrated, under pressure or humiliated because they are no longer able to cope with the everyday demands of life. It takes longer for a person with dementia to process information and respond to a situation - in words or in actions. It is therefore common for them to feel pressured.
  • Feel their independence and privacy are threatened because they are forced to accept help with intimate functions such as washing, dressing or going to the toilet. These are areas of life which have been private since childhood. It is not surprising that these situations become particularly stressful.
  • Feel they are being judged or criticized because they have forgotten something or made a mistake in completing an everyday task.
  • Feel bewildered or frightened because there is too much noise or too many people around them or there has been a change in a familiar routine. All these things can be hard for a person with dementia to manage.

The person may also react aggressively in situations where they:

  • Feel anxious or threatened because they are no longer able to recognize certain places or people. They may be convinced that they are in the wrong place or that a relative is a stranger who must have broken into their home.
  • Feel frightened because of a sudden noise, sharp voices, abrupt movements or a person approaching them without warning from behind.
  • Feel discomfort, pain, boredom or thirst.


Brian Willie, Caring For An Aggressive Alzheimer's Patient, Jan. 24, 2008

Alzheimer's Society - UK

APA Reference
Staff, H. (2021, December 20). Alzheimer's Disease and Aggressive Behavior, HealthyPlace. Retrieved on 2024, July 13 from

Last Updated: January 5, 2022

Medically reviewed by Harry Croft, MD

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